Snubbing mechanism for gyrating extractors



May 22, 1956 2,746,569

SNUBBING MECHANISM FOR GYRATING EXTRACTORS G. P. CASTNER 3 SheetsSheet 1Filed NOV. 28, 195] IN VEN TOR. 65024: P Chan/1? firromrsrs PIE 5 May22, 1956 G. P. CASTNER 2,746,569

SNUBBING MECHANISM FOR GYRATING EXTRACTORS Filed Nov. 28, 1951 I5Sheets-Sheet 2 QMZMM/ y 1956 ca. P. CASTNER 2,746,569

SNUBBING MECHANISM FOR GYRATING EXTRACTORS Filed Nov. 28, 1951 3Sheets-Sheet 3 FIGS INVENTOR. GEORGE E? Cur/vex BY W 4% Arm N578SNUBBING MECHANISM FOR GYRATING EXTRACTORS George P. Castner, WebsterCity, Iowa, assignor, by mesne assignments, to Gamble-Skogmo, Inc.,Minneapolis, Minn., a corporation of Delaware Application November 28,1951, Serial No. 258,710

3 Claims. (Cl. 188-1) tion that machines of this general nature includea washing mechanism which is mounted for tilting, gyrating motion abouta center pivotal support, with means for centering this assembly and forsnubbing or frictionally damping the vibrations and gyrations thereof.In practice the clothes are washed in a tub by means of a suitableagitator and upon completion of the washing cycle the washing liquid iscentrifugally extracted from the clothes by spinning the tub. Due to thefact that the load as represented by the wet clothes is almost neverexactly evenly distributed about the spin axis, the spinning assembly issubject to very considerable eccentric vibrations due to this unbalancedload. This problem is well recognized in the industry and many attemptshave been made to suppress the vibrations and absorb them before theyare transmitted to the outer casing of the machine, which is, of course,very undesirable and which in many cases has made it necessary to boltthe machine to the-floor. In the machine of Patent No. 2,513,844 thegyrating assembly, or inner frame, is tiltably mounted at its lower endin a suitable bearing carried by the stationary outer frame of themachine and the inner assembly is yieldably centered by horizontally,radially arranged springs. In addition, the rotating receptacle or tubis provided with a heavy balancing ring, but it is further necessary tosnub or frictionally damp the eccentric vibrations and gyrations inorder to keep these motions within reasonable bounds.

.For this purpose in the earlier machine radiallyarranged snubber armsemanate from the inner gyrating assembly and at their outer ends carrysnubber disks or friction shoes, between which are located plates whichare secured to the stationary outer assembly. The respective snubberdisks are then frictionally pressed into engagement with the plates bycoil springs placed upon bolts piercing the snubbing assemblies, all asdescribed in detail in the earlier patent. Such snubbing mechanismis-effective, but

the present invention improves upon this snubbingmechanism, both as tosimplicity and more important as to efiectiveness in its function ofsnubbing and restraining the gyrations and vibrations.

In the previous snubbing mechanism it has been found difficult toequalize the effective spring tension upon the actual snubbing elementsor disks and there is very little control over the horizontal travel ofthe snubbers as the '1 inner spin assembly gyrates. It will, of course,be realized that the centering springs will influence this travel, in

Y addition to which the flywheel effect of the balancing ring UnitedStates Patent I I v v 2,746,569 Patented May 22,1956

upon the tub will also have a bearing on this motion, but it is verydesirable that the snubbing mechanism itself have a minimum travel in aradial or horizontal direction so that the mechanism will, in and ofitself, operate to better advantage in restricting the gyrating motionsof the inner assembly. It is accordingly the primary object of myinvention to provide an improved snubbing mechanism which, while in manyrespects is similar to that disclosed in the mentioned patent, is soconstructed and arranged that the effective spring tension upon theindividual snubbers may be pre-set and maintained far more evenly andwherein the snubber springs are so arranged that the tension upon thecoacting friction surfaces will be increased upon relative motion ofthese surfaces in any direction as the inner assembly gyrates. Thus itwill be seen that the greater the amplitude of the gyrating movement thegreater will be the effective braking tension of the snubber-springs,with the result that the travel will be minimized.

Another object of my present invention is to provide a snubbingmechanism which is simpler and less expensive to manufacture than thatdisclosed in the earlier patent.

These and other more detailed and specific objects will be disclosed inthe course of the following specification, reference being had to theaccompanying drawings, in which- Fig. l is an elevational view,partially in vertical cross section, of a washing machine including aninner gyrating frame or washer assembly and outer stationary frameassembly and showing the application thereto of a snubbing mechanismaccording to my present invention.

Fig. 2 is an enlarged fragmentary horizontal sectional view takensubstantially along the line 22 in Fig. 1 and showing in plan view oneof the improved snubbing mechanisms.

Figs. 3 and 4 are respectively vertical sectional views along the lines3-3 and 44 in Fig. 2.

Fig. 5 is a composite plan and side view of one of the parts of thissnubbing mechanism.

Referring now more particularly and by reference characters to thedrawing, the washing machine as shown in Fig. 1 thereof conventionallyincludes an outer stationary frame assembly, designated generally at A,and an inner, tiltably supported gyrating frame or washer assembly,designated generally at B. As noted hereinbefore this assembly isessentially the same as that disclosed in Patent No. 2,513,844, and asshown in Fig. l the outer stationary frame includes a base frame Cenclosed in a suitable housing D and within the upper part of which is aliquid containing receptacle E. Disposed within the latter is a rotaryreceptacle or tub F which receivesthe clothes and washing liquid and theclothes are washed by means of the agitator G. The tub F and agitator Gare carried by a generally upright and centrally located drive assemblyand the latter is tiltably supported in a resilient bearing H held in abearing cup I at the lower center portion of the base frame C. Theassembly B may thus gyrate and tilt about its flexible support in thebearing H and normally the assembly is centered by means of a pluralityof radially located centering springs, one of which appears at J and allof which are, of course, stretched between the relatively movable innerand outer frame assemblies. When spinning the tub F under unbalancedload conditions, the inner assembly may gyrate about its fulcrum at thebearing H, with the gyratory motion limited in part by the 'action ofthe centering springs J and in part by the flyends of the centeringsprings J are connected by eye-bolts M and as material to the disclosureof my present invention it is to be noted that this base ring providesinwardly directed, vertically spaced, horizontal flanges or brackets Nand O which are located at some distance above the bearing H and belowthe stationary receptacle B. These brackets N and O, as they will behereinafter referred to, are also, of course, spaced radially outwardfrom the inner gyrating assembly F.

In accordance with my present invention a plurality of improved snubberor friction damper mechanisms are associated with the inner gyratingassembly B and the stationary brackets N and O and while there are threeof such assemblies, each evenly circumferentially spaced from the next,I will here show and describe only one in detail since they are allidentical in construction. Each such assembly then comprises a radiallyextending snubber arm 10, made up of flexible material such as springsteel, and secured at its inner end by bolts 11 to a suitable horizontalflange surface 12 forming part of the gyrating inner frame assembly B.The snubber arm projects from this point of rigid attachment to thegyrating assembly outward in overlapping and vertically spaced relationto the adjacent upper flange N and as seen in Fig. 2 the outer endportion of the snubber arm is considerably widened, as designated at 10Secured in spaced relation to the underside of the paddle-like widenedouter end of the arm 10 is a pair of rectangular snubber shoes 13, whichare made of brake lining or similar material and are held in place bycountersunk rivets 14 or other suitable fastening. The width of theouter end of the snubber arm is such, as compared to the correspondingdimension of the two snubber shoes 13, that the latter are spaced aparta considerable distance from the centerline of the arm or from a radiusemanating from the spin axis of the gyrating assembly B, as clearlyshown in Figs. 2 and 4. Interposed between the shoes 13 and the adjacentupper surface of the bracket N is a snubber plate 15 secured by bolts 16or other suitable means to the bracket and this snubber plate thus formsa horizontal smooth surface coacting with the snubber shoes. As hereshown the snubber plate 15 is generally rectangular in shape, with thecorners cut away, and the length of the plate cross Wise of the snubberarm is such as to place the fastening bolt 16 well out to the oppositesides of the arm. The width of the snubber plate 15, as measuredradially of the machine, is such as to provide for a considerable rangeof travel of the snubber shoes and as shown the snubber plate extendssome distance inward from the upper bracket N for this reason.

The snubber shoes 13 are pulled down against the snubber plate 15 by avertical, retractile coil, snubber spring 17 located between the upperand lower brackets N and O and having its lower end 18 hooked over theedge of the lower bracket and into an opening 19 provided therein forthis purpose. The upper bracket N and overlying snubber plate 15 arethen provided with large clearance openings 20 through which the upperend of the spring extends between the snubber shoes 13, and to receivethe upper end of the spring the snubber arm 10 is provided along itscenterline with a slot 21 spaced from the outer end 22 of the arm andaligned with a notch 23 opening through this end, as best seen in Fig.2. The slot 21 and notch 23 thus provide an intervening web 24 and theupper hooked end 25 of the spring 17 projects up through the slot 21,crosses said web outwardly and then extends back down into the notch 23,as seen in Fig. 3. Actually this hooked end 25 of the spring does notdirectly engage the snubber arm at its center and the tension of thespring is placed upon a bridge or cross arm 26, disposed crosswise uponthe arm and extending from one edge thereof to the other out over thesnubber shoes 13. The bridge 26 is formed up from sheet material and isarcuate in cross section, as seen in Fig. 3, so as to resist bendingstresses or distortion under the pull of the spring. At its center,furthermore, the bridge is formed with spaced depending lugs 27 of awidth and spacing such as to fit down into the slot 21 and notch 23while bridging the web 24. The opposite end portions of the bridge arethen formed with laterally projecting flanges 28 to rest upon the uppersurface of the snubber arm 10 and the lugs 27, by their engagement withopposite sides of the web 24, will hold the bridge in position crosswiseof the arm as clearly shown. As viewed from the outer end of the arm, ina plane crosswise of the radial axis, the bridge 26 is crowned or archedat its center and the bridge thus serves to bring the tension of thespring 17 directly out over the snubber shoes 13 and acts to equallydistribute the spring tension to and between the shoes.

In operation it will be understood that the tilting gyrations of theinner assembly B will, of necessity, cause the snubber shoes 13 to slideacross the snubber plates 15, but the tension of the snubber springs andfrictional action of the snubber shoes will yieldably resist this motionin order to snub and damp the gyrations, all as pointed out in theearlier patent. The snubber arms 10 must also, of course, besufiiciently flexible to accommodate the tilting action of the innergyrating assembly, while the openings 20 will be of such size as topermit the necessary travel of the snubber shoes without interferencefrom the springs which project upward through said openings.

It is of extreme importance, in order that the snubbing mechanism havethe desired damping effect upon the gymtions, that the movement of thesnubber shoes 13 in any direction be immediately resisted by the tensionof the snubber spring 17 and that such movement be accompanied by animmediate increase in the effective spring tension on the shoes. In theearlier snubbing mechanism hereinbefore referred to the snubber springs,since they were positioned upon bolts which held the snubbing diskstogether and traveled therewith, had only a constant spring tension onthe friction surfaces, but in the present case, since the snubbersprings 17 are stretched directly between the stationary lower bracket 0and the superimposed movable snubber arm 10 and stand vertically whenassembly B is on center, it is evident that motion of the snubber shoesin any direction will then tilt the springs and accordingly stretch themto immediately increase their effective tension on the shoes. Thus inthe case of the three circumferentially spaced snubbing mechanisms, ascontemplated by my present invention, it will be seen that all threemechanisms will continually operate to damp gyrations and vibrations inany direction and thus the mechanism will operate with utmosteffectiveness for the desired purpose. It is, of course, important thatthe snubber springs be vertically positioned for this purpose sinceotherwise, While a motion in one direction might tend to stretch thespring and increase the tension, an opposite motion would have theopposite and undesirable effect of decreasing the tension. For example,if the springs were arranged diagonally they might also be utilized tosome degree to center the gyrating assembly, but they would then losemuch of their effectiveness in the snubbing phase of their operation.

In addition, the structure as herein disclosed is extremely simple andconvenient to assemble during manufacture of the machine and the factthat short vertically positioned springs are thus used enables me, bythe proper selection of springs of good quality, to pre-set the tensionupon the individual snubbing mechanisms and to maintain this tension atan even ratio under all conditions of operation. The provision of thebridge 26 brings the spring tension out evenly over the individualsnubber shoes 13 of each mechanism so that the maximum snubbing effectis obtained and the shoes will wear in evenly and have a long usefullife.

It is understood that suitable modifications may be made in thestructure as disclosed, provided such modifications come within thespirit and scope of the appended claims. Having now therefore fullyillustrated and described my invention, what I claim to be new anddesire to protect by Letters Patent is:

1. In a clothes washing machine, an outer stationary frame, an innergyratory frame and means mounting the same in said outer frame forgyration about a normal upright axis; snubbing mechanism for resistingsuch gyration of the inner frame, comprising a base ring secured to theouter frame and surrounding the inner frame and having an inwardlyturned flange, a plurality of vertically flexible snubber arms annularlyspaced within said ring and rigidly secured to the inner frame andextending outwardly over the said flange and each having snubber shoeson its underside, a snubbing plate secured to the flange under saidsnubber shoes and these plates and the flange having registeringopenings, retractile coil springs extending vertically loosely throughsaid openings and means attaching the upper and lower ends of thesprings respectively to the snubber arms and the stationary framewhereby the tension of the springs will pull the snubber shoes downwardwith increasing pressure into frictional contact with said plates uponhorizontal displacement of said inner frame in any direction.

2. In a clothes washing machine, an outer stationary frame, an innergyratory frame and means mounting the same in said outer frame forgyration about a normal upright axis; snubbing mechanism for resistingsuch gyration of the inner frame, comprising a base ring secured to theouter frame and surrounding the inner frame and having an inwardlyturned flange, a plurality of vertically flexible snubber arms annularlyspaced within said ring and rigidly secured to the inner frame andextending outwardly over the said flange and each having snubber shoeson its underside, a snubbing plate secured to the flange under saidsnubber shoes and these plates and the flange having registeringopenings, retractile coil springs extending vertically loosely throughsaid openings and means attaching the lower ends of the springs to thestationary frame, and a bridge member attached to the upper end of eachspring and extending at its ends oppositely over the snubber shoes toequally distribute the spring tension to both shoes on each snubber arm.

3. In a clothes washing machine, an outer stationary frame, an innergyratory frame and means mounting the same in said outer frame forgyration about a normal upright axis; snubbing mechanism for resistingsuch gyration of the inner frame, comprising a base ring secured to theouter frame and surrounding the inner frame and having an inwardlyturned flange, a plurality of vertically flexible snubber arms annularlyspaced within said ring and rigidly secured to the inner frame andextending outwardly over the said flange and each having snubber shoeson its underside, a snubbing plate secured to the flange under saidsnubber shoes and these plates and the flange having registeringopenings, retractile coil springs extending vertically loosely throughsaid openings and means attaching the lower ends of the springs to thestationary frame, a bridge member attached to the upper end of eachspring and extending at its ends oppositely over the snubber shoes toequally distribute the spring tension to all the shoes on each snubberarm, the snubber arms being notched to clear the upper ends of thesprings and the bridge members having lugs to fit into said notches tohold said members in proper relation to the snubber shoes.

References Cited in the file of this patent UNITED STATES PATENTS781,732 MacFarlane Feb. 7, 1905 1,564,659 Xardell Dec. 8, 1925 1,763,682Wallace June 17, 1930 1,772,602 Dunham Aug. 12, 1930 2,268,204 DunhamDec. 30, 1941 2,396,105 Kirby Mar. 5, 1946 2,454,112 Woodson Nov. 16,1948 2,513,844 Castner et al July 4, 1950 2,534,194 Emmert et al. Dec.12, 1950 2,585,107 Geldhof Feb. 12, 1952 2,614,410 Kirby Oct. 21, 1952FOREIGN PATENTS 475,199 Great Britain 1937 674,698 Germany Apr. 1939

